A new and threatened species of internally inseminating seasonal killifish of Campellolebias (Cyprinodontiformes: Rivulidae) endemic to a continental island in the Atlantic Forest, Southern Brazil

Zoologischer Anzeiger, Journal Year: 2025, Volume and Issue: unknown

Published: March 1, 2025

Language: Английский

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Independent evolution of satellite DNA sequences in homologous sex chromosomes of Neotropical armored catfish (Harttia)

Communications Biology, Journal Year: 2025, Volume and Issue: 8(1)

Published: March 30, 2025

Abstract The Neotropical armored catfish Harttia is a valuable model for studying sex chromosome evolution, featuring two independently evolved male-heterogametic systems. This study examined satellitomes—sets of satellite DNAs—from four Amazonian species: H. duriventris (X 1 X 2 Y), rondoni (XY), punctata and villasboas Y). These species share homologous chromosomes, with their satellitomes showing high number DNAs (satDNAs), primarily located on centromeres or telomeres, varying by species. Each revealed distinct satDNA profile, independent amplification homogenization events occurring, suggesting an important role these repetitive sequences in differentiation short evolutionary time, especially recently originated chromosomes. Whole painting bioinformatics that without heteromorphic specific (HviSat08-4011) amplified the same linkage group associated ancestral system. Such sequence has partial homology ZP4 gene responsible formation egg envelope, which its discussed. indicates chromosomes have diverged rapidly, recently, content, transposable elements playing minor when compared roles autosomal evolution.

Language: Английский

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Darwinian shortfall and macroecological patterns in genetic data of Tocantins-Araguaia basin fishes

Neotropical Ichthyology, Journal Year: 2025, Volume and Issue: 23(1)

Published: Jan. 1, 2025

Abstract Genetic information is crucial for species identification, population genetics structure, evolutionary relationships, and biodiversity monitoring. It helps address gaps related to Linnean (taxonomic uncertainty) Darwinian (phylogenetic knowledge) shortfalls. Understanding these can guide data collection reduce This study focuses on compiling genetic 748 fish in the Tocantins-Araguaia basin, examining number of unique genomic regions individual sampled per species. We also investigated factors that determine availability by linking it with macroecological predictors. Our findings reveal fewer than one-third endemic have resources available. The shortfall - lack phylogenetic knowledge a key factor limiting data, experiencing more this having less information. underscores need increased sampling better assess biological like structure.

Language: Английский

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A new species of Characidium (Characiformes: Crenuchidae) from the Iguaçu National Park, Rio Iguaçu basin, Paraná, Brazil

Journal of Fish Biology, Journal Year: 2025, Volume and Issue: unknown

Published: April 9, 2025

Abstract A new species of Characidium is described from the Iguaçu National Park, Brazil. The can be diagnosed congeners by absence conspicuous vertical bars, blotches and spots along sides body, presence a scaled isthmus adipose fin, series scales below lateral line thin dark midlateral stripe. reticulated colour pattern melanophores posterior edge found in similar to that C. xanthopterum , with which it presents 4.2% genetic distance. Morphological molecular analyses showed species, supported multiple delimitation methods (Assemble Species Automatic Partitioning, General Mixed Yule Coalescent method, Poisson Tree Process its Bayesian implementation). sister group itarare occurs Paranapanema river basin (upper Paraná river). Despite being located within conservation unit, known only two creeks, raising concerns about long‐term conservation.

Language: Английский

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Speciation Rates of Freshwater Fish Across the Americas Vary With Environmental Heterogeneity and Dispersal Ability

Journal of Biogeography, Journal Year: 2025, Volume and Issue: unknown

Published: April 17, 2025

ABSTRACT Aims Species richnesses show marked spatial trends, but the contribution of speciation rates (SpecRates) to these trends is less clear. The roles environmental heterogeneity (topography and climate), glaciation, dispersal ability, times colonise, speciate large‐scale variation in SpecRates freshwater fish faunas are assessed. Location Atlantic Pacific coast drainages North, Central, South America. Taxon Fish. Methods Published information was compiled on SpecRates, phylogenies, colonisation times, species geographic distributions, migratory behaviour fishes 582 catchments. effects topographic climatic factors, including glaciation vagility, three rate metrics were examined using boosted regression tree models. Results Mean differ five‐fold across drainage regions with glaciation. highest Nearctic decline southwards, drainages, between Neotropical basins. Assemblage vary percentage species, heterogeneity, time, age. High associated postglacial recolonisation by rapidly speciating diadromous Neotropics for resident potamodromous higher than species. dispersing into an area more migratory, occur further north, have wider distributions diversifying situ. Endemicity recently colonised increases time levels. Main Conclusions Spatial temporal topography climate generate differences connectivity which, coupled abilities overcome barriers, result different areas.

Language: Английский

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